1. Field of the Invention
The present invention relates to an electric control system that can control a transmission and a receive of log data among a plurality of control units through a communication line, and relates to an electric control unit.
2. Description of Related Art
In a case of using an electric control unit (hereinafter referred to as ECU) to control an operation of an engine for a vehicle, the ECU includes: a recording medium such as a RAM that records detection data calculated on the basis of a detection signal from a sensor for detecting an operating state of the vehicle; log data generated in a case of determining that an abnormality has occurred in operation data representing a control amount of a fuel injection amount, an ignition timing and the like which are calculated on the basis of the detection data; log data configured by diagnostic result data which is obtained at regular intervals by diagnosing whether or not an abnormality has occurred in the ECU body, or the like.
For example, in Japanese Patent Application Laid-Open No. H09-160602 (1997) shows a system having a plurality of ECUs. When one of the ECUs in the system detects an occurrence of a failure, the one of the ECU records control signals before and after the detection of the failure and transmits abnormal signals to other ECU. Meanwhile, the “other ECU” having received the abnormal signal records control signals before and after the reception of the abnormal signal. In this manner, it is possible to record control signals at the time of the abnormality, by the plurality of ECUs.
Further, in Japanese Patent Application Laid-Open No. 2002-193070, when an abnormality occurs in one ECU, this ECU collects control signals of other related ECUs through a network and records the collected signals in a built-in recording means along with own abnormal information. In this manner, it is possible to collectively record related abnormal information, to help analysis for the cause.